Field of the Invention
The invention is in the field of energy storage technology.
Related Art
Energy storage is important in many applications. These include, backup power, portable electronic devices, and vehicles. One type of energy storage is the lithium ion battery. This battery is currently used in vehicles and portable electronics. There is, however, a need for improved energy storage capacity.
For example, prior art cathodes used in lithium ion batteries suffer from low energy density (i.e. lithium cobalt oxide ˜180 mAh/g) when compared to the best available anode materials (silicon ˜4000 mAh/g). To alleviate this issue, there has been focus on developing lithium-air batteries, at the expense of additional complexity of new separators and chemistries to support the battery coming in contact with air. One of the developments is to rely upon the reversible formation/decomposition reaction of Li2O2 at the cathode upon cycling. [e.g., “A Reversible and Higher-Rate Li—O2 Battery”, Science, vol. 337, pgs 563-566]. One issue with the technique described in this paper is that the materials used to catalyze the reaction (gold), has a weight that creates an effective energy density of ˜300 mAh/g. The technology also suffers from poor charging rates. The charging rates being dependent at least in part on catalyst surface area.